JP2019502263A - How to interconnect solar cells - Google Patents

Abstract

The photovoltaic module comprises a rear substrate having a plurality of conductive interconnects on its top. The conductive interconnect includes a first contact area and a second contact area. The photovoltaic module further comprises a plurality of photovoltaic cells comprising a front electrode disposed on the front surface of the photovoltaic layer on the top of the rear electrode on the top of the support substrate. A plurality of rear vias extending through the support substrate of the first cell form an electrical contact between the rear electrode and the second contact region, and the second cell support substrate, the rear electrode, and the photovoltaic cell. A plurality of front vias extending through the power layer form an electrical contact between the front electrode and the first contact region and are not in electrical contact with the rear electrode and the P side of the photovoltaic layer. So as to be insulated.
[Selection] Figure 1A

Description

[Cross-reference of related applications]
This application claims priority from US Patent Application Publication No. 14 / 994,889, filed January 13, 2016, entitled “Method of Interconnecting Solar Cells”. The disclosure of this prior application is incorporated herein by reference in its entirety.

  The present invention relates generally to photovoltaic cells, and more particularly to interconnecting photovoltaic cells to photovoltaic modules.

  Solar cells have become a widely used technology for converting light energy into electrical energy. Arrays of solar cells can be interconnected and assembled into solar modules or solar panels to achieve the collective current and collective voltage generated by the individual solar cells. One widely approached approach to interconnecting solar cells is to superimpose two solar cells, such as an upper cell and a lower cell, to achieve an electrical connection. In a typical solar cell configuration, the rear electrode of the upper cell is electrically connected to the front electrode of the lower cell. In this technique, a plurality of solar cells are interconnected in series.

  More specifically, the metal contacts disposed on the front and rear sides of the photovoltaic (PV) layer of the solar cell form a front electrode and a rear electrode, respectively. The rear electrode is disposed between the PV layer and the non-conductive substrate layer. Thus, when the two batteries partially overlap each other, the non-conductive substrate is disposed between the rear electrode of the upper battery and the front electrode of the lower battery. To provide electrical continuity between two overlapping cells, create a via on the substrate, typically in the form of a resin, paste, or ink during the filling process, and a conductive material that cures after the curing process Fill the vias.

  In practice, rear vias usually tend to overfill with conductive material to prevent void formation inside the via, which can potentially lead to poor contact. However, especially when two solar cells are stacked and pressed together to integrate, by filling the rear vias with excess conductive material, the conductive material from the vias is uncontrolled from the side. There is a tendency to cause overflow (smear). Undesirably, the conductive material overflow can reach the front and rear electrodes of another solar cell (eg, the lower solar cell), bridge, and cause a short circuit.

  Conventionally, to solve this problem, an insulating material is deposited around the solar cell, followed by a curing procedure. For the mechanical integrity of the solar module, an insulating adhesive can be applied to join both the overlapping solar cells and so that the conductive material overflow described above does not cause a short circuit.

  Furthermore, a series of solar cells in a solar module needs to be protected from mismatching of the characteristics of the interconnected solar cells so that the energy generation capabilities of the interconnected solar cells are not dissipated. When solar cells are arranged in an overlapping structure, one method is to place a ribbon-like conductor in a location corresponding to several solar cells, so that a group of solar cells in a solar module is also referred to as a bypass diode. Is to connect. The ribbon conductor provides electrical contact between the contact terminals of the diode and the series of solar cell contact terminals to be bypassed.

  Therefore, it eliminates the overlap between the solar cell and the associated insulation of the individual solar cells, reduces the overall thickness of the solar panel due to the overlap between the solar cell and the associated insulation, and the solar module A series of solar cells and diodes need to be conveniently connected.

  In an exemplary embodiment according to the present disclosure, a photovoltaic cell includes a photovoltaic layer configured to convert light energy into electrical energy, and a front portion disposed on a first side of the photovoltaic layer. A conductive layer and a rear conductive layer disposed on the second side of the photovoltaic layer. The second side is opposite the first side, and the front conductive layer and the rear conductive layer are configured to conduct current generated from the photovoltaic layer to an external circuit. The photovoltaic cell further includes a support substrate disposed below the back conductive layer, and the back via extends through the support substrate and is distributed with conductive material to form electrical contact with the back conductive layer. The front via extends through the support substrate layer, the rear conductive layer, and the photovoltaic layer to distribute the conductive and insulating materials. The insulating material insulates the conductive material from electrical contact with the rear conductive layer and the P side of the photovoltaic layer, and the conductive material makes electrical contact with the front conductive layer.

  In another exemplary embodiment according to the present disclosure, a photovoltaic module includes a rear substrate and a plurality of conductive interconnects disposed on top of the outer surface of the rear substrate. The conductive interconnect has a first contact area and a second contact area. The photovoltaic module further includes a plurality of photovoltaic cells electrically coupled together at the top of the outer surface of the rear substrate. The photovoltaic cell comprises a front electrode disposed on the front surface of the photovoltaic layer on the top of the back electrode on the top of the support substrate. The photovoltaic cell also extends through the support substrate to form a plurality of rear vias that form electrical contact with the rear electrode, and extends through the support substrate, the rear electrode, and the photovoltaic layer to provide a front end. A plurality of front vias that form electrical contact with the partial electrodes and are insulated so as not to be in electrical contact with the rear electrode and the P side of the photovoltaic layer. The first contact region of one of the plurality of conductive interconnects is electrically connected to the plurality of front vias of the first photovoltaic cell of the plurality of photovoltaic cells. And the second region of the conductive interconnect is electrically coupled to a plurality of rear vias of the second photovoltaic cell of the plurality of photovoltaic cells.

  In yet another exemplary embodiment according to the present disclosure, a method for interconnecting photovoltaic cells is provided. The photovoltaic cell includes a front electrode disposed on the photovoltaic layer disposed on the rear electrode on the support substrate, and a plurality extending through the support substrate to form electrical contact with the rear electrode. Extending through the rear via and the support substrate, rear electrode, and photovoltaic layer to form electrical contact with the front electrode and in electrical contact with the rear electrode and the P side of the photovoltaic layer And a plurality of front vias that are insulated so as not to be insulated. The method includes attaching a conductive interconnect on the outer surface of the back substrate, the conductive interconnect having a first contact area and a second contact area. The method also includes attaching the first photovoltaic cell to overlap the first contact region of the conductive interconnect, wherein the plurality of front vias of the first photovoltaic cell include: Electrically coupled between the first contact region of the conductive interconnect and the front electrode of the first photovoltaic cell. The method further includes attaching a second photovoltaic cell to overlap the second contact region of the conductive interconnect, wherein the plurality of rear vias of the second photovoltaic cell are electrically conductive. Electrically coupled between the second contact region of the conductive interconnect and the rear electrode of the second photovoltaic cell.

  Embodiments of the present invention will be better understood by reading the following detailed description when taken in conjunction with the accompanying drawings, in which like reference characters designate like elements.

2 is a plan view of an integrated configuration of two exemplary photovoltaic cells each electrically coupled to a conductive interconnect through a respective via structure according to an embodiment of the present disclosure. FIG. 1B is a cross-sectional view of the integrated configuration of FIG. 1A taken along line AA. FIG. 1B is a cross-sectional view of the integrated configuration of FIG. 1A taken along line BB. FIG. 2 is a plan view of an exemplary PV cell having a plurality of front vias and a plurality of rear vias from the front surface of the PV cell, according to one embodiment of the present disclosure. FIG. 2B is a cross-sectional view of the PV cell of FIG. 2A taken along line AA. FIG. 2B is a cross-sectional view of the PV cell of FIG. 2A taken along line BB. FIG. 2 is a cross-sectional view of a portion of an exemplary PV cell showing a front via insulated with an insulating material, according to one embodiment of the present disclosure. FIG. FIG. 6 shows a cross-sectional view of a portion of another exemplary PV cell showing a front via insulated with an insulating material, according to one embodiment of the present disclosure. FIG. 6 shows a cross-sectional view of a portion of another exemplary PV cell showing a front via insulated with an insulating material, according to one embodiment of the present disclosure. 1 is a cross-sectional view of a portion of an exemplary PV cell showing an insulated front via with a conductive material dispensed, according to one embodiment of the present disclosure. FIG. 2 is a cross-sectional view of a portion of an exemplary PV cell showing a rear via that has been distributed with conductive material, in accordance with an embodiment of the present disclosure. FIG. 2 is a cross-sectional view of a portion of an exemplary PV cell showing a differently insulated front via distributed with conductive material, according to one embodiment of the present disclosure. FIG. FIG. 3 is a plan view from the rear surface of a PV cell showing a plurality of front vias and a plurality of rear vias according to an embodiment of the present disclosure. 2 is a plan view of a rear substrate showing a plurality of conductive interconnects according to an embodiment of the present disclosure. FIG. FIG. 7B illustrates first and second PV cells coupled to conductive interconnects on the top of the rear substrate of FIG. 7A, according to one embodiment of the present disclosure. FIG. 7B is a plan view of an exemplary PV module illustrating a plurality of PV cells interconnected by the plurality of conductive interconnects of FIG. 7A according to one embodiment of the present disclosure. 1 is a plan view of an exemplary PV module showing a diode electrically coupled to an interconnect extension according to one embodiment of the present disclosure. FIG.

  Reference will now be made in detail to the preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. While the invention will be described in conjunction with the preferred embodiments, it will be understood that the preferred embodiments are not intended to limit the invention to these embodiments. On the contrary, the invention is intended to cover alternatives, modifications, and equivalents, which may be included within the spirit and scope of the invention as defined by the appended claims. Furthermore, in the following detailed description of embodiments of the present invention, numerous specific details are set forth in order to provide a thorough understanding of the specification. However, one skilled in the art will recognize that the invention may be practiced without these specific details. In other instances, well-known methods, procedures, components, and circuits have not been described in detail as not to unnecessarily obscure aspects of the embodiments of the present invention. For clarity, the method may be expressed as a sequence of numbered steps, but numbering does not necessarily define the order of the steps. It should be understood that some of the steps may be skipped, performed in parallel, or performed without the requirement to maintain strict sequence order. The drawings illustrating embodiments of the present invention are semi-schematic, not to scale, and in particular, some of the dimensions are for clarity and are exaggerated in the drawings. Has been. Similarly, for ease of explanation, the line of sight of the drawing is generally shown in a similar orientation, although this depiction of the drawing is largely arbitrary. In general, the present invention can be operated in any orientation.

[Explanation of technical terms]
However, it should be borne in mind that these and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. As will be apparent from the following discussion, unless otherwise specified, discussions that utilize terms such as "process" or "access" or "execute" or "store" or "render" throughout the present invention Is recognized as referring to the activities and processing of a computer system or similar electronic computing device, which is physically (inside the registers and memory of the computer system and other computer readable media) Manipulating data expressed as electrical) quantities and into other data similarly expressed as physical quantities within a computer system memory or register, or other such information storage, transmission equipment, or display equipment Convert. When a component appears in some embodiments, using the same reference number means that the component is the same component as shown in the original embodiment.

[Method of interconnecting solar cells]
Embodiments of the present invention are described with respect to interconnecting solar cells to solar modules or solar sub-modules. Examples of such solar cells include, but are not limited to, photovoltaic devices, optoelectronic devices, semiconductor devices, and any electronic device (eg, diode, light emitting diode (LED), etc.). Examples of such metal contacts for optoelectronic devices include any electrode pattern of optoelectronic devices, including but not limited to finger bus bar configurations.

  In this specification, the terms “solar module” and “photovoltaic (PV) module” are used interchangeably, and the terms “solar cell” and “PV cell” are used interchangeably. As used herein, the terms “front”, “rear”, “top”, and “relative to the intended orientation of the PV cell when the PV cell is installed in place for energy conversion” Use "bottom". For example, the front side of the PV cell is intended to face toward sunlight.

  The present disclosure is not limited to any specific configuration, structure, dimensions, geometry, material composition, fabrication process, or application of solar cells. In some embodiments, the PV cell PV layer is based on GaAs, copper-indium-gallium-selenium (CIGS), cadmium telluride (CdTe), amorphous silicon, amorphous microcrystalline tandem, thin film polycrystalline silicon, etc. One or more thin film sub-layers may be included. The substrate of the solar cell may be flexible or rigid, and may be made from a polymer, silicon, glass or the like. For example, the substrate is flexible and includes a pressure sensitive adhesive (PSA) layer and a polyethylene terephthalate (PET) layer.

  In some embodiments, an array of PV cells is electrically coupled in series to achieve higher power generation, where, for example, the front electrode of each PV cell is connected to another PV cell. Connected to the rear electrode. FIG. 1A is a plan view illustrating an integrated configuration of two representative PV cells 110 and 120, each electrically coupled to a conductive interconnect 130, according to one embodiment of the present disclosure. PV cell 110 and PV cell 120 each have a top surface and a back surface (not shown). The conductive interconnect 130 also has a top surface 130-1 and a back surface (not shown). PV cells 110 and 120 partially overlap with interconnect 130 to couple to the top surface 130-1 of conductive interconnect 130 at the rear surface of PV cells 110 and 120. Conductive material distributed in the plurality of rear vias of the PV cell 110 provides electrical contact between the PV cell 110 and the interconnect 130 and is distributed in the plurality of front vias of the PV cell 120. The electrically conductive material provides electrical contact between the PV cell 120 and the interconnect 130.

  FIG. 1B is a cross-sectional view of the integrated configuration of FIG. 1A taken along line AA. The PV cell 110 includes a front metal layer 111, a PV layer 112, a rear metal layer 113, and a non-conductive support substrate layer 114. The PV cell 110 further includes a plurality of rear vias 115 in the support substrate layer 114. The rear via 115 extends through the substrate layer 114 and exposes a portion of the rear metal layer 113 of the PV cell 110. The rear via 115 is distributed with a conductive material that provides electrical connection between the rear metal layer 113 of the PV cell 110 and the interconnect 130.

  1C is a cross-sectional view of the integrated configuration of FIG. 1A taken along line BB. The PV cell 120 includes a front metal layer 121, a PV layer 122, a rear metal layer 123, and a nonconductive support substrate layer 124. The PV cell 120 further includes a plurality of front vias 126. The front via 126 extends within the stack of the substrate layer 124, the rear metal layer 123, and the PV layer 122 and exposes a portion of the front metal layer 121 of the PV cell 120. The front via 126 is distributed conductive material that provides electrical connection between the front metal layer 121 of the PV cell 120 and the interconnect 130, thereby interconnecting the PV cell 110 electrically in series. Connecting. The front via 126 is also distributed with an insulating material (not shown) that electrically insulates the conductive material so that it is not electrically connected to the rear metal layer 123 and the PV layer 122.

  Typically, the conductive material is distributed from the back surface 118 of the substrate 114 into the back via 115 after the back metal layer 113 is integrated with the substrate 114. The conductive material and the insulating material around the walls of the front via 126 are also distributed into the front via 126 from the rear surface 128 of the substrate 124 after the rear metal 123 is integrated with the support substrate 124. The It is actually helpful to distribute an excess amount of conductive material into the via to ensure a void-free electrical contact through the via. The conductive material can also be an adhesive that couples the PV cell 110 and the PV cell 120 to the interconnect 130.

  Each component layer of a PV cell as shown in FIG. 1 may have a variety of suitable material compositions, and can be integrated into the PV cell, whether fabricated by any suitable technique known in the art. Recognize that you may. Also, the order in which the various constituent layers are integrated varies depending on the particular embodiment. The support substrate layer can also include one or more adhesive material layers that bond the support substrate to the back metal layer. For example, the PSA layer can bond the substrate layer to the back metal layer.

  FIG. 2A is a plan view of an exemplary PV cell having a plurality of front vias and a plurality of rear vias according to one embodiment of the present disclosure. A comb-shaped front electrode is shown on the front surface 202 of the PV cell 200 to include a bus bar 201A and a plurality of fingers 201B. The plurality of front vias 203 are arranged in the horizontal direction and directly below the bus bar 201 </ b> A, and have a plurality of corresponding openings (indicated by broken circles) on the rear surface (not shown) of the PV cell 200. The plurality of rear vias 204 are arranged in the lateral direction between the finger electrodes and have a plurality of corresponding openings (shown by dashed circles) on the rear surface (not shown) of the PV cell 200.

  FIG. 2B is a cross-sectional view of a portion of the PV cell of FIG. 2A taken along line AA showing the front via structure. From rear to front, the PV cell 200 includes a support substrate layer 212, a rear metal layer 210, a PV layer 208, and a front metal layer 201A. Support substrate layer 212 is shown to include a PSA layer 212B and a PET layer 212A. Front via 203 extends through the stack of support substrate layer 212, rear metal layer 210, and PV layer 208 to expose a portion of the front electrode. In this example, the exposed front metal layer is part of the bus bar 201A.

  2C is a cross-sectional view of a portion of the PV cell of FIG. 2A taken along line BB showing the rear via structure. From rear to front, the PV cell 200 includes a support substrate layer 212, a rear metal layer 210, a PV layer 208, and a front metal layer 201B. Support substrate layer 212 is shown to include a PSA layer 212B and a PET layer 212A. The rear via 204 extends through the support substrate layer 212 to expose a portion of the rear metal layer 210.

  The back via 204 can be formed by drilling through the support substrate layer 212 by laser ablation or any suitable technique known in the art. Laser ablation followed by wet etching through the support substrate layer 212 and extending through the back metal layer 210 and PV layer 208, or by any suitable technique known in the art. A partial via 203 can be formed. In some embodiments, a laser can be used to remove through the support substrate layer 212 and a portion of the back metal layer 210. At this time, wet etching can be used to remove any remaining back metal layer 210 and extend through the PV layer 208. The shapes, dimensions, patterns, and number of front and rear vias shown herein are only representative.

  FIG. 3A is a cross-sectional view of an exemplary front via with an insulating material dispensed according to one embodiment of the present disclosure. As shown in FIG. 3A, the front via 304 of the PV cell 300 has an inner surface 306 surrounded by a stack 302 comprised of the support substrate, rear metal layer, and PV layer of the PV cell 300. The insulating wall 308 is formed over the entire height of the laminate 302 and the insulating material is applied over the inner surface 306 such that the void 307 is formed inside the front via 304 surrounded by the insulating wall 308. Distribute. Insulating material 308 insulates the rear metal layer and the P side of the PV layer so as not to make electrical contact with the conductive contacts inside void 304. The thickness of the insulating wall 308 covers a portion of the front metal layer 303 exposed by the front via 304, but leaves the exposed portion 305 of the front metal layer 303 uncovered by the insulating material.

  3B and 3C are cross-sectional views of representative front vias with distributed insulating material according to another embodiment of the present disclosure. As shown in FIG. 3B, the front via 352 of the PV cell 350 is filled with an insulating material 360 such that the inner surface 356 of the front via 352 is covered with the insulating material 360. Insulating material 360 may cover part or all of front metal layer 353 exposed by front via 352. As shown in FIG. 3C, a void 354 is formed, for example, by using a laser to remove through the insulating material 360 to remove the central portion of the insulating material and expose a portion 355 of the front metal layer 353. can do. The remaining portion of the insulating material 360 forms an insulating wall 358 so that the conductive contact inside the cavity 354 does not make electrical contact with the rear metal layer and the P side of the PV layer of the PV cell 350. To.

  FIG. 4A is a cross-sectional view of an exemplary front via that has been insulated as shown in FIGS. 3A-3C and then distributed conductive material according to one embodiment of the present disclosure. PV cell 400 includes a substrate layer 410, a rear metal layer 412, a PV layer 414, and a front metal 416. The conductive material 406 is distributed inside the insulating wall 404 of the front via 402 of the PV cell 400 and makes electrical contact with the front metal layer 416 at a portion 408. The conductive material 406 provides electrical connection between the front metal layer 416 at one end and a conductive contact (not shown) at the other end toward the substrate layer 410.

  FIG. 4B is a cross-sectional view of an exemplary rear via as shown in FIG. 2C with a conductive material dispensed, according to one embodiment of the present disclosure. The conductive material 456 is distributed inside the rear via 452 of the PV cell 400 and makes electrical contact with the rear metal layer 412 at a portion 458. The conductive material 456 provides electrical connection between the back metal layer 412 at one end and a conductive contact (not shown) at the other end toward the substrate layer 410. Conductive materials 406 and 456 can be the same material or different materials. Conductive material can be dispensed into the back and front vias by implantation, deposition, evaporation, or any other suitable dispensing process known in the art.

  FIG. 5 is a cross-sectional view of an exemplary front via distributed with conductive material and insulated with insulating material, according to one embodiment of the present disclosure. The insulating material insulates the back metal layer and the conductive material distributed inside the front via so that it does not make electrical contact with the P side of the PV layer, and the support substrate layer is made of non-conductive material. As it is made, the conductive material distributed inside the front via can contact the back metal layer and the support substrate layer as long as it is insulated from the P side of the PV layer. As shown in FIG. 5, the front via 502 of the PV cell 500 has an insulating wall 504 that extends through the PV layer 514, through the rear metal layer 512, and into the substrate layer 510. In this example, the insulating wall 504 does not extend to the entire stack of the PV layer 514, the rear metal layer 512, and the support substrate layer 510, but the stack of the PV layer 514 and the rear metal layer 512, or the support substrate layer 510. Cover only a portion. The conductive material 506 is distributed inside the front via 502 that is insulated by the insulating wall 504 and in electrical contact with the front metal layer 516 at the portion 508. Conductive material 506 provides electrical connection between the front metal layer 516 at one end and a conductive contact (not shown) at the other end toward the substrate layer 510.

  It will be appreciated that the size and mode of thickness of the layers, front vias, and rear vias are determined not only by the configuration of the solar cells but also by the need for interconnect processing. For example, the thickness of the substrate is about 100 μm, the thickness of the rear metal layer is in the range of about 3 μm to 20 μm, the thickness of the PV layer is in the range of about 2 μm to about 5 μm, and the thickness of the rear via The diameter ranges from about 300 μm to about 400 μm, and the diameter of the front via is about 1 mm or less as required.

  However, the present disclosure is not limited by the material composition, configuration, and arrangement of the front and rear electrodes of each PV cell. For example, the front electrode is made, for example, from a metal strip mainly composed of Cu having a thickness of about 5 μm. The PV layer typically comprises a single layer or a stack of thin films, with an overall thickness much less than 10 μm.

  In some embodiments, the conductive material is a conductive adhesive used to provide electrical contact and / or mechanical bonding between the PV cell and the conductive interconnect. The conductive material can take the form of an ink, paste, or resin and may be composed of Ag-epoxy. However, the present disclosure is not limited to any specific material composition distributed in the front and rear vias.

  In some embodiments, the insulating material is PSA or ethylene vinyl acetate (EVA). For example, the PSA can be heated to a liquid state and then distributed to the inner sidewalls of the front via to form an insulating wall, leaving a void inside the insulating wall. Further, the liquid PSA can be distributed in the entire space of the front via so that the inner side wall of the front via is covered. The PSA can be cured by a curing process using UV light or heat.

  FIG. 6 is a plan view from the rear surface 602 of an exemplary PV cell 600 having a plurality of front vias and a plurality of rear vias. A bus bar and a plurality of fingers arranged on the opposite side of the PV cell 600 are indicated by broken lines. The front via 604 has a circular shape and includes an internal conductive material 604-1 surrounded by an insulating wall 604-2. In order to bond the PV cell 600 to the external interconnect (not shown) at the rear surface 602, a plurality of bonding adhesive regions 608 can be configured between the plurality of front vias 604. The rear via 606 also has a circular shape and includes a conductive material 606-1 distributed inside the rear via 606. In order to bond the PV cell 600 to the external interconnect (not shown) at the rear surface 602, a plurality of bonding adhesion regions 608 can also be configured between the plurality of rear vias 606.

  The conductive material distributed inside the front via 604 and the rear via 606 not only electrically connects the PV cell 600 to another conductive contact, but also mechanically connects the PV cell 600 to the conductive contact. It can be a conductive adhesive to bond. In some embodiments, a portion of the front via 604 and rear via 606 may be non-conductive and may be used primarily to provide a mechanical bond between cells. Material can be dispensed. In some other embodiments, a portion of the front and back vias for containing the bonding adhesive may not need to extend to the front or back metal layer. The shape, size, pattern, and number of front vias, rear vias, bonding adhesion areas, bus bars, and conductive fingers are only representative and are any shape suitable for interconnecting PV cells at the rear surface , Size, pattern, or number.

  FIG. 7A is a plan view of a rear substrate showing a plurality of interconnects according to one embodiment of the present disclosure. The back substrate 700 has a front surface 701 for receiving a plurality of PV cells interconnected to the PV module. A plurality of conductive interconnects 702 are disposed on the outer surface 701. A connector 704 can be disposed on the upper side and the bottom side of the rear substrate 700 as an end connector for the entire PV module. Alternatively, the interconnect 704 can be configured as an end connector of the PV module.

  FIG. 7B shows a first PV cell 710 coupled to a conductive interconnect to a second PV cell 720 on the outer surface 701 of the back substrate 700, according to one embodiment of the present disclosure. Interconnect 702 has a first contact region 702-a at the bottom and a second contact region 702-b at the top. The first PV cell 710 has a front surface 714 and a rear surface 712, a top side 716 and a bottom side 718. The rear surface 712 houses a plurality of openings for a plurality of front vias (not shown) and a plurality of rear vias (not shown). The top side 716 is the side on which the bus bar is placed on the front surface 714, and the corresponding front via is configured directly below the bus bar. The bottom side 718 is the side on which a plurality of rear vias are configured.

  The second PV cell 720 can have the same structure as the first PV cell, ie, the second PV cell 720 has a front surface 724, a rear surface 722, a top side 726, and a bottom side 728. Can have. The rear surface 722 houses a plurality of openings for a plurality of front vias (not shown) and a plurality of rear vias (not shown). The top side 726 is the side on which the bus bar is placed on the front surface 724, and the corresponding front via is configured directly below the bus bar. The bottom side 728 is the side on which a plurality of rear vias are configured.

  As shown in FIG. 7B, the first PV cell 710 disposed on the top of the outer surface 701 of the rear substrate 700 in contact with the rear surface 712 of the PV cell 710 is a first contact region 702-of the interconnect 702. Oriented to abut the top of a and partially overlap the interconnect 702 on the top side 716. The second PV cell 720 is shown to be disposed on the outer surface 701 of the rear substrate 700 and the top of the rear surface 722 of the PV cell 720. The second PV cell 720 is oriented to contact the top of the second contact region 702-b of the interconnect 702 and partially overlap the interconnect 702 on the bottom side 728.

  Upon contact, the conductive material dispensed into the plurality of front vias is a front metal (not shown) of the first PV cell 710 and a first contact region 702-a of the conductive interconnect 702. An electrical connection is formed between the two. Upon contact, the conductive material distributed in the plurality of rear vias is between the rear metal (not shown) of the second PV cell 720 and the second contact area 702-b of the conductive interconnect 702. To make an electrical connection. Accordingly, the front metal of the first PV cell 710 is electrically coupled to the rear metal of the second PV cell 720 through the conductive interconnect 702, and the first PV cell 710 and the second PV cell 720. To achieve a series connection.

  Interconnect 702 can be any conductive material suitable for connecting PV cells. For example, the interconnect 702 can be made from Cu, Au, Al, or an alloy. In some embodiments, the strip of interconnect 702 can be bonded to the outer surface 701 of the back substrate 700 by bonding an adhesive such as TPU. In other embodiments, the interconnect 702 can be formed by applying a conductive paste of Cu, Au, Al, or a composite thereof to the top of the outer surface 701 of the rear substrate 700. Typically, the interconnect thickness is about 20 μm.

  The back substrate 700 can be any material suitable for supporting the PV module. The rear substrate 700 can also be a thermal plastic or composite plastic such that the PV cells of the PV module are mechanically bonded to the outer surface of the rear substrate. For example, the back substrate 700 can be made from PVB, PVE, or PE, or any suitable material known in the art.

  FIG. 7C is a plan view of an exemplary PV module formed by a plurality of PV cells interconnected by a plurality of conductive interconnects, according to one embodiment of the present disclosure. In this exemplary PV module 750, along the horizontal direction, the first contact region and the second contact region of the conductive interconnect 702 each overlap two PV cells in the same orientation. Along the vertical direction, the PV cell is connected to two interconnects on its respective top side (front via side) and bottom side (rear via side). In this example, the two connectors 704 are each arranged as a p-contact connector and an n-contact connector of the PV module 750. Since the connector 704 couples to the PV cell at only one contact area at the PV module boundary, the width of the connector 704 is half of the interconnect 702.

  FIG. 7D is a plan view of an exemplary PV module having a diode electrically coupled to the PV module, according to one embodiment of the present disclosure. In this example, the interconnect 702 of the PV module 760 is shown as having an extension tab 764 for electrically connecting one terminal end (n-type end) of the diode 762 to the interconnect 702. Has been. The other terminal end (p-type end) of the diode 762 is electrically connected to the connector 704-1 on the uppermost side of the PV module 760. The diode 762 conducts current when one or more PV cells connected between the connector 704-1 and the interconnect 702 are reverse-biased due to light shielding or other mismatch effects. Soldering or conductive adhesive, or expansion tab 764 to the diode and intermediate conductive strip or material to electrically couple the diode to connector 704-1 or any suitable technique known in the art Thus, the diode 762 can be electrically coupled to the expansion tab 764 and the connector 704-1. An expansion tab 764 can be coupled to the outer surface 761 of the rear substrate of the PV module 760 in the same manner that the conductive interconnect is coupled to the rear substrate. The number of expansion tabs and diodes can be configured with any number suitable to protect the PV cell from shading damage.

  FIG. 7D shows a PV module with PV cells connected in series to provide the desired voltage between connector 704-1 and connector 704-2, but interconnect 702 also provides the desired current. PV cells can be provided that form connections in parallel to provide or in series-parallel combinations. The shape, relative size, and number of conductive interconnects configured for the PV module on the top of the back substrate should be any shape, size, or number suitable for assembling the PV module Can do. Furthermore, the p-contact and n-contact of the PV cell to the external circuit are both on the back side of the PV cell, i.e. on the non-incident side of the PV cell, so Greater tolerances can be achieved for larger areas that overlap with the contact area. The wider the overlapping region, the thinner the interconnect, and the higher the tolerance for displacement with respect to the placement of the PV cell on the conductive interconnect.

  While certain preferred embodiments and methods have been disclosed herein, variations and modifications of such embodiments and methods may be made without departing from the spirit and scope of the invention. It will be apparent to those skilled in the art from the foregoing disclosure. It is intended that the present invention be limited only to the extent required by the appended claims and the rules and principles of applicable law.

Claims (20)

A photovoltaic cell,
A photovoltaic layer configured to convert light energy into electrical energy;
A front conductive layer disposed on a first side of the photovoltaic layer;
A rear conductive layer disposed on a second side of the photovoltaic layer, wherein the second side is opposite the first side, and the front conductive layer and the rear conductive layer are: A rear conductive layer configured to conduct current generated from the photovoltaic layer to an external circuit;
A support substrate layer disposed below the photovoltaic layer;
With
A rear via extends through the support substrate, is distributed conductive material, and makes electrical contact with the rear conductive layer;
A front via extends through the support substrate layer, the rear conductive layer, and the photovoltaic layer, and distributes a conductive material and an insulating material, and the insulating material includes the rear conductive layer, and the light Insulating the conductive material so as not to be in electrical contact with the P side of the electromotive force layer, the conductive material forming electrical contact with the front conductive layer;
Photovoltaic cell.   In order to form an insulating wall, the insulating material is distributed on sidewalls of the photovoltaic layer, the rear conductive layer, and the support substrate layer of the front via, and the conductive material is disposed inside the insulating wall. The photovoltaic cell of claim 1, wherein the photovoltaic cell is distributed.   The photovoltaic cell of claim 2, wherein the insulating wall covers the sidewall of the front via in the region of the photovoltaic layer and the rear conductive layer.   The photovoltaic cell of claim 1, wherein the front via is formed by laser ablating through the support substrate layer to the rear conductive layer and wet etching through the photovoltaic layer. A photovoltaic module,
A rear substrate,
A plurality of conductive interconnects disposed on top of an outer surface of the rear substrate, each conductive interconnect comprising a plurality of conductive interconnects comprising a first contact region and a second contact region; A connection,
A plurality of photovoltaic cells electrically coupled together, each photovoltaic cell being disposed on the front surface of the photovoltaic layer on the top of the rear electrode on the top of the support substrate; A plurality of rear vias extending through the support substrate to form electrical contact with the rear electrode, and the plurality of front vias comprising the support substrate, the rear electrode, and the light A plurality of photovoltaic cells extending through the photovoltaic layer to form electrical contact with the front electrode and insulated from electrical contact with the rear electrode and the P side of the photovoltaic layer. A power cell;
With
A first contact region of one of the plurality of conductive interconnects is connected to the plurality of front vias of the first photovoltaic cell of the plurality of photovoltaic cells. Electrically coupled, and the second contact region of the conductive interconnect is electrically coupled to the plurality of rear vias of a second photovoltaic cell of the plurality of photovoltaic cells;
Photovoltaic module.   The light of claim 5, wherein the first contact region of the conductive interconnect is electrically coupled to the plurality of front vias by a conductive material distributed within the plurality of front vias. Electromotive force module.   The photovoltaic of claim 5, wherein the second contact region of the conductive interconnect is electrically coupled to the plurality of rear vias by a conductive material distributed in the plurality of rear vias. module.   6. The front via of the plurality of front vias is formed by laser ablating through the support substrate layer to the rear electrode and wet etching through the photovoltaic layer. The photovoltaic module as described.   Distributing insulating material on the photovoltaic layer, the back electrode and the sidewall of the support substrate of the front via of one photovoltaic cell of the plurality of photovoltaic cells to form an insulating wall The photovoltaic module according to claim 5, wherein a conductive material is distributed inside the insulating wall.   The photovoltaic module according to claim 9, wherein the insulating wall covers the sidewall of the front via in a region of the photovoltaic layer and the rear electrode.   The photovoltaic module of claim 5, wherein one conductive interconnect of the plurality of conductive interconnects comprises an extension portion electrically coupled to a diode.   The photovoltaic module according to claim 5, wherein the rear substrate is a thermal plastic that joins the plurality of photovoltaic cells to the outer surface of the rear substrate. A method of interconnecting photovoltaic cells, the photovoltaic cell comprising a front electrode disposed on a photovoltaic layer disposed on a rear electrode on a support substrate, and comprising a plurality of rear vias Extends through the support substrate and forms electrical contact with the rear electrode, and a plurality of front vias extend through the support substrate, the rear electrode, and the photovoltaic layer, and Forming an electrical contact with the front electrode and insulated from electrical contact with the rear electrode and the P side of the photovoltaic layer, the method comprising:
Attaching a conductive interconnect comprising a first contact region and a second contact region on the outer surface of the rear substrate;
Attaching a first photovoltaic cell to overlap the first contact area of the conductive interconnect, wherein a plurality of front vias of the first photovoltaic cell are electrically conductive; Electrically coupled between the first contact region of the interconnect and the front electrode of the first photovoltaic cell;
Attaching a second photovoltaic cell to overlap the second contact area of the conductive interconnect, wherein a plurality of rear vias of the second photovoltaic cell are connected to the conductive interconnect. Electrically coupled between the second contact area of a connection and the rear electrode of the second photovoltaic cell;
Including a method.   The method of claim 13, wherein the first contact region of the conductive interconnect is electrically coupled to the plurality of front vias by a conductive material distributed within the plurality of front vias. .   The method of claim 13, wherein the second contact region of the conductive interconnect is electrically coupled to the plurality of rear vias by a conductive material distributed within the plurality of rear vias.   The method of claim 13, wherein a front via is formed by laser ablating through the support substrate to the back electrode and wet etching through the photovoltaic layer.   In order to form an insulating wall, an insulating material is distributed on sidewalls of the photovoltaic layer, the rear conductive layer, and the support substrate layer of the front via, and a conductive material is distributed inside the insulating wall. The method according to claim 13.   The method of claim 17, wherein the insulating wall covers the sidewall of the front via in the region of the photovoltaic layer and the rear electrode.   The method of claim 13, further comprising forming an extension portion of the conductive interconnect and electrically coupling a diode to the extension portion.   The method of claim 13, wherein the rear substrate is a thermal plastic that joins the plurality of photovoltaic cells to the outer surface of the rear substrate.

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